"No Additive PET Tube" likely refers to a blood collection tube used in medical settings. PET stands for polyethylene terephthalate, a type of plastic commonly used in the production of laboratory equipment, including blood collection tubes.The "No Additive PET Tube" is likely designed for situations where a plain blood sample is needed, without any additives that could potentially affect the test results. These tubes are particularly useful for tests that require serum or plasma without any interference from additives.